Hi all,
I'm looking for some thoughts / understanding re how a (say) Mk2 1300 Escort saloon front suspension / spring relationship might work, especially in regard to a coil-over conversion (and I know there are some here who have done this sort of work / conversion).
The question is around how the springs are positively located on my current setup (Mk2 Escort based kitcar) and how that might change post conversion.
So, with the current / stock setup the lower spring cup is welded to the strut / leg and is 'shaped' to match the shape of the bottom of the spring to prevent the spring from rotating in the cup.
The damper rod then goes up though the spring, though a similar shaped (but inverted etc) top cup that also locates on the spring positively. This cup is located on the damper rod by the use of flats (or a 'D' not sure), it then passes though the rubber bush in the top mount and is fished of by a shaped and equally positively located fitting (that would prevent the leg pulling though the mount should the rubber bush fail).
The result of all this is that from what I can see in the HBOL and from my own vehicle, the top cup is not allowed to rotate so therefore as you steer, one spring will wind up and the other, unwind. [1]
This is further confirmed as the HBOL says after working on these legs you should slacken the top damper-rod nuts slightly, set the steering in a straight line and *then* torque and lock (peen) the nut in place.
What is happening there is the damper rod is being allowed to turn in the metal bushing that is bonded though the rubber bush and then locked to the insert (and then bush) once torqued up.
Now, if you replace the above with a coil-over conversion and assuming you have the spring to have the same pre load as the stock setup, what is to stop the springs moving on their seats as you turn and what affect might that have on the steering (centring) if they did?
What I often see mention alongside coil-over conversions is roller top mounts and this makes more sense as now the top spring cup can rotate along with the spring, as the steering is turned.
So, can anyone help me pin down exactly what *should* be done if applying one of these conversions please. Do I *have* to fit a bearing with coil-overs to prevent the chance of the springs moving on their cups (and either wearing the mountings, stressing the spring or affecting the self-centring)?
Cheers, T i m
[1] I have previously tried rotating the top spring cup on our and other (newer) vehicles and in most (all?) cases the top cup *does* freely rotate as the steering is changed.p.s. I would only be going to such as a last result and only because my current setup has offset lower cups and seem to foul what should be compatible wheels / tyres. ;-(